I’ve got an OpenWRT router, and here’s how I configured it to enable safesearch on my home network.
uci add dhcp cname uci set dhcp.@cname[-1].cname="www.google.com" uci set dhcp.@cname[-1].target="forcesafesearch.google.com" uci commit dhcp uci add dhcp cname uci set dhcp.@cname[-1].cname="www.bing.com" uci set dhcp.@cname[-1].target="strict.bing.com" uci commit dhcp uci add dhcp cname uci set dhcp.@cname[-1].cname="duckduckgo.com" uci set dhcp.@cname[-1].target="safe.duckduckgo.com" uci commit dhcp for name in www.youtube.com m.youtube.com youtubei.googleapis.com youtube.googleapis.com www.youtube-nocookie.com ; do uci add dhcp cname uci set dhcp.@cname[-1].cname="$name" uci set dhcp.@cname[-1].target="restrict.youtube.com" uci commit dhcp done service dnsmasq restart
See the configuration:
grep -A2 cname /etc/config/dhcp